Django.
We bought him as a 7 week old puppy on July 1, 2000. Every day since--literally every day--he has made me laugh. He's a goofy clown and lovable as they come.
Aw, what a cutie! One of ours is a boxer/shar pei and he is seriously silly. Sometimes he looks very serious..then he starts rolling around on his back and snorting. I laugh so hard when he plays with our other dog, Patches.